Certain fiber optic materials have been shown to have an energy sensitivity. Some fiber optic materials such as KRS-5 decrease their transmissivity with time. The rate of this degradation is accelerated by transmission of radiant energy in the mid-infrared band. Thus, it is desirable, or in some cases necessary (laser surgery, for example), to limit the energy entering or exiting the fiber to prohibit radiant energy destruction of the fiber itself.
In other instances, it is desirable to limit the total energy transmitted through a fiber to limit distal-end degradation. Such is the case in laser surgery using silica-based optical fibers, where the silica-based fiber is destroyed due to contact with the vaporizing tissue. Continued delivery of radiant energy in such cases will result in breaking the fiber and leaving sections of fiber in the patient.
In still other instances, where fibers have windows and/or contact delivery probes, maximum energy limits can prevent failure modes in these structures.
In addition, in some cases optical fibers can become degraded or damaged as a result of mechanical stresses (e.g., bending, flexing, accidental dropping, etc.) incident to their use. It may be necessary or desirable to limit the total number of uses of an optical fiber to prevent failure due to mechanical causes independent of the energy exposure of the fiber.
Accordingly, there is a need for a device which will keep an accumulated record of the usage of an optical fiber, and in addition is able to control and limit use of the fiber as desired. It is also desirable that the accumulated usage history of a fiber travel with the fiber upon disconnection and reconnection of the fiber.